Conventionally, a gripper having suction pads capable of sucking two orthogonal surfaces of a package from two directions and a linear moving mechanism configured to move the suction pads linearly is known (refer to Japanese Unexamined Patent Application, Publication No. 2016-94280, for example).
With this gripper, the package can be sucked by actuating the suction pads after the linear moving mechanism moves the suction pads so that the suction pads in the two directions are each positioned close to the two orthogonal surfaces of the package.